Method And Systems For Stick Mitigation Of Cable

ABSTRACT

A system for stick mitigation of a cable in a well includes a derrick operatively aligned with a well. The derrick supports a cable and a cable injector. The cable injector is operatively aligned with the well and the cable, and the cable injector is disengaged during normal operations.

CROSS-REFERENCE TO RELATED APPLICATIONS

None.

FIELD OF THE DISCLOSURE

The disclosure generally relates to methods and systems for stick mitigation on cable.

BACKGROUND

Cable is used in many well services. For example, cable is used to deploy tools into the well. The tension on cable during well service has increased as wells are drilled to greater depths.

Capstans are used to reduce tension on cable. The capstan, however, requires cable to bend about sheaves, and bending the cables about the sheaves can reduce the cable's working ends-fixed break strength (EFBS) to about from 60 percent to about 65 percent of the cable's rated EFBS.

A need exists, therefore, for systems and methods for stick mitigation of cable that allows cable to have a larger working EFBS, allowing greater forces to be applied to the cable if the cable, a tool string connected with the cable, or both get stuck in the well.

SUMMARY

An embodiment of a system for stick mitigation of cable in a well can include a derrick operatively aligned with the well. The derrick can support a cable, and a cable injector can be connected with the derrick. The cable injector can be operatively aligned with the well and the cable, and the cable injector can be disengaged as the cable is run into the well. In an embodiment, a drum can be used to move the cable relative to the well, and a capstan can be located between the derrick and the drum.

An embodiment of a method for stick mitigation of cable in a well can include performing a well service using cable supported by a derrick. The method can further include moving the cable relative to the well with a drum during normal operations. The method can also include engaging a cable injector to pull on the cable if the cable is stuck in the well.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts an example embodiment of a system.

FIG. 2 depicts another example embodiment of a system.

FIG. 3 depicts an example of cable injector blocks.

FIG. 4 depicts an example cable.

FIG. 5 depicts an example method.

DETAILED DESCRIPTION OF THE INVENTION

Certain examples are shown in the above-identified figures and described in detail below. In describing these examples, like or identical reference numbers are used to identify common or similar elements. The figures are not necessarily to scale and certain features and certain views of the figures may be shown exaggerated in scale or in schematic for clarity and/or conciseness.

A system for stick mitigation of cable in a well can include a derrick operatively aligned with the well. The derrick can support the cable as the cable is used to perform well services. The cable can be any cable used in well services; however, in an embodiment the cable is a wireline cable. The wireline cable can be a polymer-locked, crush-free wireline cable or any other wireline cable.

A cable injector can be connected with the derrick. The cable injector can be connected with the derrick in any manner. For example, the cable injector can be hung on the derrick and aligned with the well. The cable injector can be operatively aligned with the well and the cable. For example, the cable injector can be aligned with the cable and well allowing the cable injector to provide force to the cable that is perpendicular to the well. The cable injector can be disengaged during normal operations. Normal operations, as used herein, means that neither the cable, a tool string connected with the cable, or both are stuck in the well.

During normal operations, a drum connected with the cable can be used to move the cable relative to the well. For example, the drum can run the cable into the well and pull the cable out of the well. In an embodiment of the system, a capstan can be located between the derrick and the drum.

An example method for stick mitigation of cable in a well includes performing a well service using a cable supported by a derrick, and moving the cable relative to the well with a drum. During normal operation of the system the well service can be performed with the cable injector disengaged; however, the cable injector can be engaged to pull on the cable if the cable is stuck in the well during the well service, deployment of the cable, retrieval of the cable, or combinations thereof. The cable injector can pull on the cable with a force that is up to about 85 percent of the cables designed ends-fixed break strength.

Turning now to the FIGS. FIG. 1 depicts an example embodiment of a system.

The system 100 includes a derrick 110 operatively supporting a cable 120. For example, a plurality of sheaves can be connected with the derrick 110, and the sheaves can guide and support the cable 120. The cable 120 at one end can be connected with a service tool 122. The service tool 122 can be measurement equipment, telemetry equipment, pumping equipment, perforating equipment, other downhole equipment, or combinations thereof. For example, a combination of sensors and other downhole equipment can be assembled to form a toolstring, and the toolstring can be connected with the cable. The cable 120 at another end can be connected with a drum 140.

The drum 140 can be used to run the cable 120 into the well 160. The drum 140 can move the cable 120 relative to the well 160. The cable 120 can be used to deploy the attached service tool 122 to a desired depth so a service operation can be performed. After the service operation is performed, the drum 140 can be used to retrieve the cable 120 and the attached service tool 122.

A cable injector 130 is operatively connected with the derrick 110. The cable injector 130 can be any cable injector. A power source 170 can be in communication with the cable injector 130. The power source 170 can be an electric power source, a hydraulic power source, a pneumatic power source, or combinations thereof.

During normal operation of the system 100, the cable injector 130 is disengaged, and the drum 140 provides the force on the cable 120 that is necessary to run the cable 120 into the well 160 and pull the cable 120 out of the well 160. The cable 120, the connected service tool 122, or both may get stuck in the well 160. For example, the service tool 122 may catch on an obstruction in the well 160. Additional force may need to be applied to the cable 120 to free the cable 120, the service tool 122, or both when the cable 120, the service tool 122, or both are stuck, and normal operation of the system is no longer possible.

To provide the additional force, the cable injector 130 is engaged and the power source 170 provides power to a drive assembly of the cable injector 130. Engaging the cable injector 130 can include providing power, using the power source 170 to one or more actuators (not shown), such as linear actuators, to move a pair of cable blocks (shown in detail below) into engagement with one another. The engaged cable injector 130 can provide force to the cable 120, and the force applied to the cable 120 can be perpendicular to or substantially in line with the well 160. Accordingly, the cable 120 is pulled in a straight line by the cable injector 130. The cable injector 130 provides force until the cable 120 and the service tool 122 are free to move relative to the well, allowing normal operations to resume. Once normal operations resume, the cable injector 130 is disengaged.

FIG. 2 depicts another example embodiment of a system. The system 200 includes the derrick 110, the cable injector 130, the cable 120, and the drum 140. The power source 170 can be in communication with the cable injector 130, and the service tool 122 can be connected with the cable 120.

The system 200 can also include a capstan 150. The capstan 150 can be located between the derrick 110 and the drum 140. The capstan 150 can reduce tension on the cable 120 during normal operations. For example, as the drum 140 runs the cable 120 into the well 160 to deploy the service tool 122, the capstan 150 can reduce the tension on the cable 120 to the drum 140.

FIG. 3 depicts an example of cable injector blocks. A first cable injector block 310 and a second cable injector block 320 can cooperate to provide force to the cable 120, when the cable injector is engaged.

The first cable injector block 310 can include a first belt 314. The first belt 314 can be located on a first drive assembly (not shown). The first drive assembly can be any drive system. Illustrative drive assemblies include hydraulic systems, electric systems, and pneumatic systems. A first channel 312 can be located on the first belt 314. The first channel 312 is configured to fit about the cable 120.

The second cable injector block 320 can include a second belt 324. The second belt 324 can be disposed about a second drive assembly (not shown). The second drive assembly can be any drive system. The second belt 324 can have a second channel 322. The first channel 312 is aligned with the second channel 322 when the injector block is operatively installed on the derrick. Accordingly, the first belt 314 and the second belt 324 can engage one another when the injector block is engaged, and the first channel 312 and the second channel 322 can secure about the cable 120. The belts 314 and 324 can move and provide force to the cable 120.

The belts 314 and 324 can be made of any material that allows the belts 314 and 324 to tightly grip the cable 120 without damaging the cable 120. The material can be softer than the cable 120. Illustrative materials include wood, polymers, or metal.

FIG. 4 depicts an example cable. The example cable 120 includes a core 410, inner armor 420, and outer armor 430.

The core 410 can have any number of conductors 412. The conductors 412 can have a jacket 414 disposed thereabout. A polymer 422 can fill the core 410 and interstitial spaces between the inner armor 420 and the outer armor 430. The polymer 422 can be crush-resistant polymer. The polymer 422 locks the armor layers 420 and 430 with the jacket 414. Accordingly, the armor layers 420 and 430 are locked with the core 410. The design of the cable 120 provides a mechanically rigid, torque-balanced and crush-free wireline cable that reduces issues with core coldflow, cable rotation, plastic stretch, armor stranding, and bird-caging.

The cable 120 can be spooled under high-tension. For example the cable 120 can be spooled at a tension of about 13,000 lbf, handle instantaneous pulls of about 18,000 lbf, and with a safety margin of about 9,000 lbf.

FIG. 5 depicts an example method. The method 500 is depicted as a plurality of blocks or operations.

The method 500 includes performing a well service using a cable supported by a derrick (Block 510). The method 500 continues by moving the cable relative to the well with a drum during normal operations (Block 512). In an embodiment of the method a capstan located between the derrick and drum is used to reduce cable tension during normal operations.

The method also includes engaging a cable injector to pull on the cable if the cable is stuck in the well (Block 514). The cable can be stuck in the well when a service tool connected with the cable is stuck or the cable is otherwise stuck. The cable injector can be engaged by providing power to actuators and moving injector blocks into engagement about the cable. Power can then be delivered to a drive system connected with the cable injector, and the cable injector pulls on the cable with a force that is up to about 80 percent of the cables ends-fixed break strength. During normal operations, the cable injector is disengaged.

Although example assemblies, methods, systems have been described herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers every method, apparatus, and article of manufacture fairly falling within the scope of the appended claims either literally or under the doctrine of equivalents. 

What is claimed is:
 1. A system for stick mitigation of cable in a well, wherein the system comprises: a derrick operatively aligned with a well; a cable supported by the derrick; and a cable injector connected with the derrick, wherein the cable injector is operatively aligned with the well and the cable, and wherein the cable injector is disengaged during normal operations.
 2. The system of claim 1, wherein the cable injector is hung on the derrick.
 3. The system of claim 1, wherein the cable is a polymer-locked, crush-free wireline cable.
 4. The system of claim 1, further comprising: a drum connected with the cable, wherein the drum runs the cable in the well, and wherein the drum pulls the cable out of the well.
 5. A system for stick mitigation of cable in a well, wherein the system comprises: a derrick operatively aligned with a well; a cable supported by the derrick; a drum for running the cable into and pulling the cable out of the well; a capstan located between the derrick and the drum; and a cable injector connected with the derrick, wherein the cable injector is operatively aligned with the well and the cable, and wherein the cable injector is disengaged as the cable is run into the well.
 6. A method for stick mitigation of cable in a well, wherein the method comprises: performing a well service using a cable supported by a derrick; moving the cable relative to the well with a drum during normal operations; and engaging a cable injector to pull on the cable if the cable is stuck in the well.
 7. The method of claim 6, wherein the cable injector pulls on the cable with a force that is up to 85 percent of the cables ends-fixed break strength.
 8. The method of claim 6, wherein the cable injector is disengaged during normal operations.
 9. The method of claim 6, wherein engaging the cable injector comprises providing hydraulic power thereto.
 10. The method of claim 6, further comprising using a capstan located between the derrick and drum to reduce cable tension during normal operations. 